Plastic catheter with rubber balloon



Aug. 12, 1969 l J. L. GAGNE PLASTIC CATHETER WITH RUBBER BALLOON' YFiled April 18, 196eA IN VENTOR. (jays/'v .5. 'yz e BY v W Y wm UnitedStates Patent O 3,460,540 PLASTIC CATHETER WITH RUBBER BALLOGN Joseph L.Gagne, Warwick, RJ., assignor to Davol Inc., Providence, RJ., acorporation of Rhode Island Filed Apr. 1S, 1966, Ser. No. 543,403 Int.Cl. A61m 25/00 U.S. Cl. 12S-349 3 Claims ABSTRACT F 'IHE DISCLOSURE Aplastic catheter having a rubber tip secured to its distal end, a thinlayer of rubber latex fused to and covering the portion of the plasticcatheter adjacent its distal end, including the aforesaid tip, and aniniiatable rubber sac fused to said rubber latex layer, said plasticcatheter further comprising a plastic funnel portion secured to theproximal end of the catheter, said funnel portion having a drainagepassage in alignment with the catheter drainage lumen and an inflatingpassage in communication with the inflating lumen of the catheter.

The present invention relates generally to medical and surgical productsand is more particularly concerned with catheters.

A primary object of the instant invention is the provision of a novelcatheter of the so-called urethral or retention type, and the method ofmanufacture thereof.

Catheters of the urethral or retention type have been in use for manyyears and traditionally comprise a iiexible and resilient tubular bodyportion having elongated drainage and inflating lumens extendinglongitudinally therethrough. An opening is provided in the catheter wallextending into communication with the inilating lumen, and an inflatablesac or balloon is secured to the catheter in overlying relation withrespect to the inflating opening, whereupon introduction of uid pressurethrough the inflating lumen will cause the sac or balloon to distend.The distal end of the catheter is normally rounded and closed off, withthe exception of a drainage eye provided at said distal end in thecatheter wall in communication with the drainage lumen, said drainageeye being located distally of the aforesaid balloon or sac. At theproximal end of the catheter, funnel portions are provided incommunication with the inating and drainage lumens, respectively, thetubular body normally lbeing bifurcated adjacent its proximal endwhereupon the proximal ends of the inilating and drainage lumen extendangularly from each other. Catheters of this general type areillustrated in United States Patents Nos. 2,248,934 and 2,308,484.

Catheters of the general type described supra have been conventionallymade of rubber, the usual manufacturing technique involving a series oflatex dips, much in the manner described in United States Patent No.2,320,157, for example. Although rubber latex catheters of this typehave proven to be quite satisfactory in operation and use, it has beenfound that certain advantages are achieved by making the body portion ofthe catheter of a clear plastic material. More specifically, in urethralcatheters constructed of rubber latex, it has been found that after acertain degree of usage, there is a build-up of calcium salts in thedrainage lumen of the catheter, which build-up serves to reduce thedrainage capacity of the catheter, and in extreme cases might evenocclude the catheter so as to completely block off drainage. Byconstructing the catheter body portion of a nontraumatic, flexible andnontoxic plastic, the catheter will function substantially aseffectively as the conventional rubber latex catheter, but, at the sametime, the plastic will resist the undesirable build-up of calcium saltsmentioned above. In addition, where the catheter body portion isconstructed of plastic, it is pos- 3,460,540 Patented Aug. 12, 1969sible to provide a larger diameter drainage lumen for a given outerdiameter; and hence, without increasing the outer diameter of thecatheter, by using plastic it is possible to provide a catheter havinggreater drainage capacity in addition to being resistant to undesirablebuild-up of calcium salts such as would tend to decrease the drainagecapacity of the catheter. Also, by making the body portion of thecatheter of a clear, transparent plastic, added advantages are obtainedin that the catheter can be visually inspected to insure that properdrainage is taking place, etc.

On the other hand, even though it has been found desirable to provide aurethral catheter having a plastic body portion, it has, at the sametime, been found that plastic balloons or sacs do not function nearly aseffectively as the conventional rubber latex balloons or sacs.Specifically, plastic balloons or sacs do not have the resilience orelastic memory of rubber latex, and hence it has been found in practicethat in operation and use rubber latex balloons or sacs are much moreeilicient and durable than plastic balloons.

It is therefore a primary object of the instant invention to provide aurethral catheter having a plastic body portion in combination with arubber latex balloon.

It has also been found that where a plastic tip is fused or otherwiseapplied to the distal end of the plastic catheter, a relatively hard andheavy mass exists at said tip. On occasion, this relatively hard distaltip has been found to be a source of internal irritation to the patient,sometimes causing bladder spasms.

It is therefore another object of this invention to provide a catheterhaving a plastic body, but having a distal tip on said body that is of asoft, resilient material, such as soft rubber, and that is of hollowconfiguration for added softness.

Another important object of this invention is the provision of a noveland improved method of manufacturing a combination plastic and rubbercatheter.

Another object is the provision of a combination plastic and rubbercatheter, and a method of making same, having novel and improved meansforI associating and assemblying the inflating and drainage funnels withthe catheter body` Other objects, features and advantages of theinvention will become apparent as the description thereof proceeds whenconsidered in connection with the accompanying illustrative drawings.

In the drawings which illustrate the best mode presently contemplatedfor carrying out the instant invention:

FIG. 1 is a front elevational View of a catheter constructed inaccordance with the instant inevntion;

FIG. 2 is an elevation section, on an enlarged scale, of the cathetershown in FIG. 1;

FIG. 3 is an elevational view, partly in section, showing the plastictubing from which my catheter is made;

FIG. 4 is an elevational view of the tubing shown in FIG. 3 aftercertain steps have been performed during the manufacture of my catheter;

FIG. 5 s an elevational view of the tubing after further steps have beenperformed;

FIG. 6 is a sectional view of the funnel unit which forms a part of myinvention;

FIG. 7 is a perspective view of the balloon or sac per se which forms apart of my invention;

FIG. `8 is a section taken on line 8-8 of FIG. 1; and

FIG. 9 is a section taken on line 9--9 of FIG. 6.

Referring now to the drawings and more particularly to IFIGS. l and 2thereof, there is shown generally at 10 a catheter which is constructedin accordance with the instant invention. The catheter 10 comprises anelongated body portion 12 having a drainage lumen 14 and an inflatinglumen 16 extending longitudinally therethrough. The body portion 12 isconstructed of any suit-v able nontraumatic7 exible and nontoxicplastic, such as polyvinyl chloride, and may be formed by an suitablemanufacturing technique, although extruding is preferred. As will beseen most clearly in FIG. 3, the body portion 12 is actually a length oftubing, cut to the desired length, and open at its opposite extremities.The distal end 18 of body portion 12 is provided with a rounded hollowtip 20 of soft rubber or the like that is secured to the adjacentextremity of body portion 12 by any suitable means such as cementing. Aswill be seen, the tip 2t) closes off the distal extremity of bodyportion 12, although an opening 22 is provided in the wall of bodyportion 12 adjacent the distal extremity thereof. It will be understoodthat opening 22 is in communication with drainage lumen 14 so as topermit introduction thereto of fluids to be drained, all in a mannerwell known in the art.

Secured adjacent the distal end of body portion 12, by a techniquehereinafter to be described in detail, is a rubber latex balloon or sac24, it being noted that said balloon extends around body portion 12 andis in communication with inllating lumen 16 by means of opening 26extending through the wall of the body portion. It will be understoodthat as fluid under pressure is forced through inating lumen 16, it willbe introduced into balloon 24 through opening 26, whereupon the balloonwill be caused to distend to assume the broken-line position shown inFIG. 2. Thus, when a patient is catheterized ination of balloon 24 willretain the catheter within the patient, all in a manner well known inthe art.

As will be seen, and as will be understood, the opening 22 isnecessarily located distally of balloon 24. It will be furtherunderstood that the provision of the soft hollow rubber tip 20 at thedistal end of the catheter comprises an important feature of the instantinvention since it has been found that such a tip is nontraumatic in useWhereas a relatively hard plastic distal tip sometimes causes bladderspasms in the patient.

At its proximal end 28, body portion 12 receives a funnel unit generallyindicated at 30 (FIG. 6). The funnel unit 30 is preferably molded of anysuitable plastic, such as by injection molding, and comprises a maintubular portion 32 having a lower bore 34 adapted to snugly and slidablyreceive therein the upper end of body portion 12. The unit 30 furthercomprises an integral, angularly extending funnel portion 36 having aninflating bore 38 extending therethrough into communication with bore34. As will be seen, the tubular portion 32 of funnel unit 30 isprovided with an upper bore 40 in alignment and communication with lowerbore 34.

In order that lumen 16 may properly function as an inflating lumen fordistension of balloon 24, it is necessary that the upper extremity oflumen 16 be closed oi, and this is done by any suitable means, such asby pressing therein a plug 42. Slightly below the plug 42 there isprovided in the wall of body 12 an aperture 44 communicating with theupper end of lumen 16. Now, when the funnel unit 30 is slidably mountedon the upper or proximal end of body portion 12, it will be seen thatbore 40 is in communication with drainage lumen 14, while at the sametime the unit 30` is aligned so that inflating bore 38 is in alignmentwith the aperture 44 whereupon communication is provided between bore38` and lumen 16. It will thus be seen that with the funnel unit 30flxedly secured to the proximal end of body portion 12, which securementmay be effected by any suitable means, such as solvent fusing or thelike, introduction of fluid under pressure through bore 38 will functionto distend the balloon or sac 24, all in a well-known fashion. At thesame time, the desired drainage through catheter is provided via opening22, lumen 14, and bore 40.

Since the body portion 12 is constructed of a suitable plastic, such aspolyvinyl chloride, and since the balloon or sac 24 is constructed ofrubber latex, certain unusual manufacturing techniques and proceduresare employed during the manufacture of the catheter 10, and hence theoverall method of making catheter 10 will now be described. The initialsteps in to provide the body portion 12 having the drainage lumen 14 andinflating lumen 16 extending longitudinally therethrough, as shown inFIG. 3. As hereinbefore described, the body portion 12 is constructed ofa suitable plastic, such as polyvinyl chloride, and is preferably madeby an extrusion process. The next step is to close olf the distal end 18of body portion 12 by applying thereto a rounded hollow tip 20 of softrubber or the like. This may be done by any suitable means, such as bycementing the tip 20 to the extremity of the body portion 12. Since itis desired that the tip 20 be hollow for added softness, the tip may bemost easily made by molding.

A suitable dipping form, such as metal rod 46, is then inserted intodrainage lumen 14, and the distal portion of body 12 is then dipped intoa suitable adhesive, such as a neoprene adhesive. The depth to which thebody portion 12 is dipped into this adhesive is not critical, althoughin practice approximately half the length of the body portion 12 ispreferably dipped. The body portion 12 is then removed from the adhesivedip and allowed to thoroughly dry, after which it is again dipped toapproximately the same depth, this time in a rubber latex bath. The bodyportion is then removed and the latex is allowed to coagulate or cure,after which the same latex dip is again repeated. This results in aninner latex layer 48 being formed around the bottom half of the outersurface of body portion 12, including rubber tip 20.

The eye 26 is now cut through the wall of body portion 12 intocommunication with inating lumen 16, and then a separate rubber latexsleeve 24a is slid upwardly over the body portion 12 until the eye 26 issubstantially centered with respect thereto. It will be understood thatthe sleeve 24a makes a relatively snug resilient engagement with bodyportion 12. At this point, the body portion 12, with the sleeve 24amounted thereon, is again dipped into a latex bath, removed, allowed tocure or coagulate, and then this dipping and curing step is againrepeated. This results in the outer latex layer 50 being formed, itbeing understood that above and below the sleeve 24a the layers 48 and50 actually fuse to form one laye-r 52. After the last latex dip andcuring, the outer surface of body portion 12, and particularly the partthereof that has been subjected to the aforesaid latex dips, isoxidized, such as by chlorination, to eliminate any surface tackiness.The body portion 12 is then slidably removed from form 46.

At this point, the opening 22 is provided through body portion 12 intocommunication with drainage lumen 14, it being important that theopening 22 be located below or distally of balloon 24.

The next step is to close olf the upper or proximal end of inating lumen16, and this may be done by any suitable means, such as by forcingtherein a rigid plug 42 of vinyl. The aperture or opening 44 is thenprovided in the wall of body portion 12 so as to provide an entrance toinflating lumen 16, it being noted that aperture 44 is located justbelow plug 42. The separately manufactured injection molded funnel unit30 is now ready for assembly and securement to the proximal end of bodyportion 12, as hereinbefore described. The outer surface of the proximalend portion of body 12 may be coated with a suitable solvent, as shownat 54 in FIG. 5, whereupon when the unit 30 is slidably engagedthereover, it will be rigidly fused in place. As hereinbefore described,when the unit 30 is secured to body portion 12, bore 40 is in alignmentand communication with drainage lumen 14, while inflating bore 38communicates with inflating lumen 16 due to its alignment with aperture44.

It will therefore be seen that there has been provided in accordancewith the instant invention a catheter capable of accomplishing all ofthe foregoing objects. Specifically,

the structure of catheter 10, and the method of making same, enable thehereinbefore enumerated benefits and advantages of a plastic bodyportion to be achieved, while at the same time obtaining the benefitsand advantages of a rubber latex balloon or sac.

While there is shown and described herein certain specific structureembodying the invention, it will be manifest to those `skilled in theart that various modifications and rearrangements of the parts may bemade Without departing from the spirit and scope of the underlyinginventive concept and that the same is not limited to the particularform herein shown and described except insofar as indicated by the scopeof the appended claims.

What is claimed is:

1. A catheter comprising an elongated, flexible body constructed of anon-rubber thermoplastic material having a drainage lumen and aninflating lumen extending longitudinally therethrough, a tip secured tothe distal end of said body, a thin layer of rubber latex fused to andcovering the outer surface of said body adjacent the distal end thereofand also covering said tip, a rubber sleeve surrounding said bodyadjacent the distal end thereof and overlying said rubber latex layer, asecond rubber latex layer covering said sleeve and said iirst layerwhereby to secure the opposite ends of said sleeve to said body while atthe same time leaving the inner surface of said sleeve disconnected withrespect to said body, a first eye located between the distal end of saidsleeve and said tip in communication with said drainage lumen, and asecond eye in the wall of said body providing communication between theinterior of said sleeve and said inflating lumen, whereby when fluidunder pressure is introduced through said inilating lumen, Said sleevewill distend to form an inatable sac.

2. The catheter of claim 1 further characterized in that said inflatinglumen is closed at its proximal end, an aperture in the wall of saidbody communicating with said iniiating lumen adjacent its closed end,and a plastic funnel member telescopingly secured over the proximal endof said catheter, said funnel member having a drainage passage incommunication with the aforesaid drainage lumen and an inflating passagealigned with said aperture so as to provide communication to saidinflating lumen.

3. The catheter of claim 1 further characterized in that said tipcomprises a soft hollow rubber member secured to said body at its distalend.

References Cited UNITED STATES PATENTS 761,235 5/ 1904 Kepler 128--3492,173,527 9/1939 Agayol 12S-349 52,896,629 7/ 1959 Warr 128--3492,930,377 3/1960 Cowley 12S-344 3,112,748 12/1963 Colburn 128-3503,292,627 12/ 1966 Harautuneian 12S-349 OTHER REFERENCES Lancer, #7371,Dec. 5, 1964,11. 12138.

DALTON L. TRULUCK, Primary Examiner

